
Reversals, Refunds, and Chargebacks: Decoding the Payment Lifecycle
Three words every payment professional uses — and confuses. Each lives at a different point in the settlement lifecycle, under a different protocol, with radically different …
Payments architecture · EMV · AI systems
I’m Vincent Bevia. I work in payments at MultiSafepay (part of Ant Group), and I’ve spent years focused on POS architecture, EMV, and cryptography. I’m also the author of Point-of-Sale Systems Architecture: A Practical Guide to Secure, Certifiable POS Systems and The Obsolescence Paradox: Why the Best Engineers Will Thrive in the AI Era.
This blog is my space to share what I’m thinking about, learning, and discussing: POS systems, EMV, Payment Security, and, increasingly, about AI in general and how AI is reshaping this field. I also draw on my background in Electrical Engineering and Telecommunications — information theory, stochastic processes, and thermodynamics — the technical foundations that sit beneath much of this work.
Less corporate, more personal. Opinions, reflections, and the kind of things I’d talk about over coffee.
If you’re building payment technology — or just curious about how it all fits together — welcome.
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Three words every payment professional uses — and confuses. Each lives at a different point in the settlement lifecycle, under a different protocol, with radically different …

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